String / Character Conversion Question

[anon]

How can following two statement be the same?

(1) using System.l1001

(2) using System.Globaliz ation;

That is, how does the compilier know these two representations , at the using
declaration level, are the same?

Thanks.

[Jon Skeet [C# MVP]]

Re: String / Character Conversion Question

anon <anon@hotmail.c om> wrote:[color=blue]
> How can following two statement be the same?
>
> (1) using System.l1001
>
> (2) using System.Globaliz ation;
>
> That is, how does the compilier know these two representations , at the using
> declaration level, are the same?[/color]

It doesn't, as far as I know. Do you have an example which leads you to
suspect that they are the same?

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[Jon Skeet [C# MVP]]

Re: String / Character Conversion Question

anon <anon@hotmail.c om> wrote:[color=blue]
> How can following two statement be the same?
>
> (1) using System.l1001
>
> (2) using System.Globaliz ation;
>
> That is, how does the compilier know these two representations , at the using
> declaration level, are the same?[/color]

It doesn't, as far as I know. Do you have an example which leads you to
suspect that they are the same?

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[anon]

Re: String / Character Conversion Question

It's from an Obfuscation example. I want to know how this is possible in
the first place.




"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1af22c 2652dc8ae798a72 8@msnews.micros oft.com...[color=blue]
> anon <anon@hotmail.c om> wrote:[color=green]
> > How can following two statement be the same?
> >
> > (1) using System.l1001
> >
> > (2) using System.Globaliz ation;
> >
> > That is, how does the compilier know these two representations , at the[/color][/color]
using[color=blue][color=green]
> > declaration level, are the same?[/color]
>
> It doesn't, as far as I know. Do you have an example which leads you to
> suspect that they are the same?
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too[/color]

[anon]

Re: String / Character Conversion Question

It's from an Obfuscation example. I want to know how this is possible in
the first place.




"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1af22c 2652dc8ae798a72 8@msnews.micros oft.com...[color=blue]
> anon <anon@hotmail.c om> wrote:[color=green]
> > How can following two statement be the same?
> >
> > (1) using System.l1001
> >
> > (2) using System.Globaliz ation;
> >
> > That is, how does the compilier know these two representations , at the[/color][/color]
using[color=blue][color=green]
> > declaration level, are the same?[/color]
>
> It doesn't, as far as I know. Do you have an example which leads you to
> suspect that they are the same?
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too[/color]

[Jon Skeet [C# MVP]]

Re: String / Character Conversion Question

anon <anon@hotmail.c om> wrote:[color=blue]
> It's from an Obfuscation example. I want to know how this is possible in
> the first place.[/color]

Unless the obfuscator is also obfuscating the system libraries, I don't
see how those two *are* going to be equivalent.

Of course, the obfuscator could have decided to change all namespaces
to System.XXX in order to confuse people - in which case it's worked!

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[Jon Skeet [C# MVP]]

Re: String / Character Conversion Question

anon <anon@hotmail.c om> wrote:[color=blue]
> It's from an Obfuscation example. I want to know how this is possible in
> the first place.[/color]

Unless the obfuscator is also obfuscating the system libraries, I don't
see how those two *are* going to be equivalent.

Of course, the obfuscator could have decided to change all namespaces
to System.XXX in order to confuse people - in which case it's worked!

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[anon]

Re: String / Character Conversion Question

This is where I saw it. So I looked and I saw they started to change the
names at the system level and then I said, how did they manage to do this.

http://www.semdesigns.com/Products/Obfuscators/CSharpObfuscationExample.html

"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1af239 2cdd02e8ee98a72 d@msnews.micros oft.com...[color=blue]
> anon <anon@hotmail.c om> wrote:[color=green]
> > It's from an Obfuscation example. I want to know how this is possible[/color][/color]
in[color=blue][color=green]
> > the first place.[/color]
>
> Unless the obfuscator is also obfuscating the system libraries, I don't
> see how those two *are* going to be equivalent.
>
> Of course, the obfuscator could have decided to change all namespaces
> to System.XXX in order to confuse people - in which case it's worked!
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too[/color]

[anon]

Re: String / Character Conversion Question

This is where I saw it. So I looked and I saw they started to change the
names at the system level and then I said, how did they manage to do this.

http://www.semdesigns.com/Products/Obfuscators/CSharpObfuscationExample.html

"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1af239 2cdd02e8ee98a72 d@msnews.micros oft.com...[color=blue]
> anon <anon@hotmail.c om> wrote:[color=green]
> > It's from an Obfuscation example. I want to know how this is possible[/color][/color]
in[color=blue][color=green]
> > the first place.[/color]
>
> Unless the obfuscator is also obfuscating the system libraries, I don't
> see how those two *are* going to be equivalent.
>
> Of course, the obfuscator could have decided to change all namespaces
> to System.XXX in order to confuse people - in which case it's worked!
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too[/color]

[Jon Skeet [C# MVP]]

Re: String / Character Conversion Question

anon <anon@hotmail.c om> wrote:[color=blue]
> This is where I saw it. So I looked and I saw they started to change the
> names at the system level and then I said, how did they manage to do this.
>
> http://www.semdesigns.com/Products/O...onExample.html[/color]

They basically can't, as far as I can tell - not without also providing
an obfuscated version of the system libraries themselves. If they've
done that, then that's a different matter. Not that creating obfuscated
*source* code is a particularly useful thing anyway, IMO. They've said
how clever they are for removing line breaks, converting text using
\uxxxx format etc - all of which is pointless when, for the most part,
obfuscation is used for *binaries*, not source: just compiling and then
decompiling would remove all the protection there apart from the name
changes.

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[Jon Skeet [C# MVP]]

Re: String / Character Conversion Question

anon <anon@hotmail.c om> wrote:[color=blue]
> This is where I saw it. So I looked and I saw they started to change the
> names at the system level and then I said, how did they manage to do this.
>
> http://www.semdesigns.com/Products/O...onExample.html[/color]

They basically can't, as far as I can tell - not without also providing
an obfuscated version of the system libraries themselves. If they've
done that, then that's a different matter. Not that creating obfuscated
*source* code is a particularly useful thing anyway, IMO. They've said
how clever they are for removing line breaks, converting text using
\uxxxx format etc - all of which is pointless when, for the most part,
obfuscation is used for *binaries*, not source: just compiling and then
decompiling would remove all the protection there apart from the name
changes.

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[anon]

Re: String / Character Conversion Question

Do you think these guys know something we don't know? At least for changing
the names to system classes?

But in regards to obfuscating source code, let's say if you did compile it
and then decompiled it.

The decompiled version would like or be similar to the source code which
would be obfuscated anyway.

The name changes would be, at least to me, a somewhat considerable hurdle to
figure out or use the source code in the first place. You would have only a
glimmer of an idea of what the source code did as you could not read that
anyway.




"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1af243 01fe7a213a98a72 e@msnews.micros oft.com...[color=blue]
> anon <anon@hotmail.c om> wrote:[color=green]
> > This is where I saw it. So I looked and I saw they started to change[/color][/color]
the[color=blue][color=green]
> > names at the system level and then I said, how did they manage to do[/color][/color]
this.[color=blue][color=green]
> >
> >[/color][/color]
http://www.semdesigns.com/Products/O...onExample.html[color=blue]
>
> They basically can't, as far as I can tell - not without also providing
> an obfuscated version of the system libraries themselves. If they've
> done that, then that's a different matter. Not that creating obfuscated
> *source* code is a particularly useful thing anyway, IMO. They've said
> how clever they are for removing line breaks, converting text using
> \uxxxx format etc - all of which is pointless when, for the most part,
> obfuscation is used for *binaries*, not source: just compiling and then
> decompiling would remove all the protection there apart from the name
> changes.
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too[/color]

[anon]

Re: String / Character Conversion Question

Do you think these guys know something we don't know? At least for changing
the names to system classes?

But in regards to obfuscating source code, let's say if you did compile it
and then decompiled it.

The decompiled version would like or be similar to the source code which
would be obfuscated anyway.

The name changes would be, at least to me, a somewhat considerable hurdle to
figure out or use the source code in the first place. You would have only a
glimmer of an idea of what the source code did as you could not read that
anyway.




"Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
news:MPG.1af243 01fe7a213a98a72 e@msnews.micros oft.com...[color=blue]
> anon <anon@hotmail.c om> wrote:[color=green]
> > This is where I saw it. So I looked and I saw they started to change[/color][/color]
the[color=blue][color=green]
> > names at the system level and then I said, how did they manage to do[/color][/color]
this.[color=blue][color=green]
> >
> >[/color][/color]
http://www.semdesigns.com/Products/O...onExample.html[color=blue]
>
> They basically can't, as far as I can tell - not without also providing
> an obfuscated version of the system libraries themselves. If they've
> done that, then that's a different matter. Not that creating obfuscated
> *source* code is a particularly useful thing anyway, IMO. They've said
> how clever they are for removing line breaks, converting text using
> \uxxxx format etc - all of which is pointless when, for the most part,
> obfuscation is used for *binaries*, not source: just compiling and then
> decompiling would remove all the protection there apart from the name
> changes.
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too[/color]

[mikeb]

Re: String / Character Conversion Question

anon wrote:[color=blue]
> This is where I saw it. So I looked and I saw they started to change the
> names at the system level and then I said, how did they manage to do this.
>
> http://www.semdesigns.com/Products/O...onExample.html
>[/color]

it's hard to know what they're doing in the example, but there are a
couple of comments that I think I can make:

1) using statements (of the namespace sort) do not get compiled down to
IL - they're used by the C# compiler to make dealing with nested
namespace names more convenient. However, the emited IL always deals
with the full typenames, so I'm not sure how a decompiler would generate
using statements, except by noting which nested namespaces are used in
the entire assembly and emitting a using statement for some or all of
those. In this case, the using statements would not magically appear in
the same order in the decompiled source as they were in the original
source as they seem to do in the example.

2) More importantly, there are no types from the System.Globaliz ation
namespace being used in the example. If no types from that namespace
are used, then the decompiler would be free to put pretty much any
namespace it wanted in place of "using System.Globaliz ation;". However,
I'm at a loss as to why it would decide to do anything with
System.Globaliz ation if no types from that namespace are used.

Looking at the example some more, I notice that the following namespaces
get renamed:

antlr
antlr.collectio ns
System.Globaliz ation
System.IO


These seem to correspond to the namespaces that don't actually get used.
That would explain why they can rename those namespaces, but it
doesn't explain why they'd have anything at all for those namespaces in
the decompiled code. Maybe I'm mistaken in my point #1, but I don't
think so.


[color=blue]
>
>
> "Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
> news:MPG.1af239 2cdd02e8ee98a72 d@msnews.micros oft.com...
>[color=green]
>>anon <anon@hotmail.c om> wrote:
>>[color=darkred]
>>>It's from an Obfuscation example. I want to know how this is possible[/color][/color]
>
> in
>[color=green][color=darkred]
>>>the first place.[/color]
>>
>>Unless the obfuscator is also obfuscating the system libraries, I don't
>>see how those two *are* going to be equivalent.
>>
>>Of course, the obfuscator could have decided to change all namespaces
>>to System.XXX in order to confuse people - in which case it's worked!
>>
>>--
>>Jon Skeet - <skeet@pobox.co m>
>>http://www.pobox.com/~skeet
>>If replying to the group, please do not mail me too[/color]
>
>
>[/color]


--
mikeb

[mikeb]

Re: String / Character Conversion Question

anon wrote:[color=blue]
> This is where I saw it. So I looked and I saw they started to change the
> names at the system level and then I said, how did they manage to do this.
>
> http://www.semdesigns.com/Products/O...onExample.html
>[/color]

it's hard to know what they're doing in the example, but there are a
couple of comments that I think I can make:

1) using statements (of the namespace sort) do not get compiled down to
IL - they're used by the C# compiler to make dealing with nested
namespace names more convenient. However, the emited IL always deals
with the full typenames, so I'm not sure how a decompiler would generate
using statements, except by noting which nested namespaces are used in
the entire assembly and emitting a using statement for some or all of
those. In this case, the using statements would not magically appear in
the same order in the decompiled source as they were in the original
source as they seem to do in the example.

2) More importantly, there are no types from the System.Globaliz ation
namespace being used in the example. If no types from that namespace
are used, then the decompiler would be free to put pretty much any
namespace it wanted in place of "using System.Globaliz ation;". However,
I'm at a loss as to why it would decide to do anything with
System.Globaliz ation if no types from that namespace are used.

Looking at the example some more, I notice that the following namespaces
get renamed:

antlr
antlr.collectio ns
System.Globaliz ation
System.IO


These seem to correspond to the namespaces that don't actually get used.
That would explain why they can rename those namespaces, but it
doesn't explain why they'd have anything at all for those namespaces in
the decompiled code. Maybe I'm mistaken in my point #1, but I don't
think so.


[color=blue]
>
>
> "Jon Skeet [C# MVP]" <skeet@pobox.co m> wrote in message
> news:MPG.1af239 2cdd02e8ee98a72 d@msnews.micros oft.com...
>[color=green]
>>anon <anon@hotmail.c om> wrote:
>>[color=darkred]
>>>It's from an Obfuscation example. I want to know how this is possible[/color][/color]
>
> in
>[color=green][color=darkred]
>>>the first place.[/color]
>>
>>Unless the obfuscator is also obfuscating the system libraries, I don't
>>see how those two *are* going to be equivalent.
>>
>>Of course, the obfuscator could have decided to change all namespaces
>>to System.XXX in order to confuse people - in which case it's worked!
>>
>>--
>>Jon Skeet - <skeet@pobox.co m>
>>http://www.pobox.com/~skeet
>>If replying to the group, please do not mail me too[/color]
>
>
>[/color]


--
mikeb